Scale & Performance
Everything filed under Scale & Performance — essays, notes, playbooks and signals.
Essays2
Notes2
Playbooks3
Measure before caching
A cache added without a measurement is a correctness risk you took for an unknown gain.
Outbox before dual writes
If a write has to land in two places, put it in one place and let a reader fan it out.
Read replicas before sharding
When read load is the bottleneck, the cheapest correct answer is almost never sharding.